在 Nodejs 中从 Dynamodb Steam 调用 AWS Lambda

Question

当我尝试从 AWS 控制台运行 lambda 函数时，代码工作正常。因为我想运行一个特定的代码只有在添加了一个新的 dynamo DB 记录时，我想运行来自 dymanoDB 流插入事件的 lambda 函数。我尝试了下面的代码，似乎 lambda 没有调用。

serverless.yml

中的权限

  - Effect: "Allow"
    Action:
      - "lambda:InvokeFunction"
    Resource: 
      - "*"

dynamoDB 流的代码

 

exports.main = async (event) => {
    const records = event.Records.filter((record) => {
        if (record.eventName.toUpperCase() === "INSERT") {
            const recordType = record.dynamodb.NewImage.type.S;

            if (recordType.toUpperCase() === "TRA") {
                 // here I capture the value for the arguments. They work fine
                 inkvokeTraLamda(keyword, key, tag);
            }  
        }
    });
};

调用lambda的函数

const AWS = require("aws-sdk");
const lambda = new AWS.Lambda({ region: "us-west-1" });
exports.inkvokeTraLamda = async function invoke(
    keyword,
    key,
    tag
) {
    const playload = {
        keyword,
        key,
        tag,
    };

    const LambdaPromise = (params) => lambda.invoke(params).promise();

    const resp = await LambdaPromise(params);
    console.log(resp);
    return resp;  
};

非常感谢您的指导。

Answer 1

而不是告诉一个 lambda 函数调用另一个。配置您相关的 Lambda 函数以侦听 DynamoDB Streams。因此，您的侦听器 Lambda 会将其添加到其事件配置中。

  events:
  - stream:
      type: dynamodb
      batchSize: 1
      # INFO: Batch Window size in seconds allows you to wait as long as 300s to build a batch before invoking a function.
      # Now, a function is invoked when one of the following conditions is met: the payload size reaches 6MB, the Batch Window reaches its maximum value, or the Batch Size reaches its maximum value.
      # With Batch Window, you can increase the average number of records passed to the function with each invocation.
      batchWindow: 5
      # This gives the option to recursively split the failed batch and retry on a smaller subset of records, eventually isolating the metadata causing the error.
      bisectBatchOnFunctionError: true
      maximumRetryAttempts: 3
      maximumRecordAgeInSeconds: 120

      arn:
        Fn::GetAtt:
          - <TableName>
          - <TableStreamArn>

一旦插入内容，您的第二个代码片段就会响应。第三个片段似乎与数据库流无关。

在 Nodejs 中从 Dynamodb Steam 调用 AWS Lambda

Invoking AWS Lambda from Dynamodb Steam in Nodejs

amazon-web-services

aws-lambda

amazon-dynamodb-streams

调用lambda的函数